Bactibilia in diseases of the biliary tract and pancreatic gland in patients older than 80 years: a STROBE-retrospective cohort study in a teaching hospital in Italy

Bile is a lipid-rich sterile solution produced in the liver that can be infected resulting in bactibilia. A higher incidence of postoperative infectious complications has been seen in patients with bactibilia. Recently, gram-negative bacteria have been linked to a tumor-associated inflammatory status. This study is a retrospective cohort study of 39 patients, who are over 80 years of age only (53.85% males and 46.15% females), hospitalized with diseases of the biliopancreatic system in one teaching hospital in Italy from January 2011 to December 2012 with a follow-up of 5 years. The most common biliary diseases after surgery were pancreatic head cancer (p < 0.0001) and gallbladder cancer (p = 0.0051), while the most common bacteria in the bile were E. coli (p = 0.0180) and Pseudomonas spp. (p < 0.0001). Uni- and multivariate linear correlation analysis revealed that patients with pancreatic head cancer had low survival times compared to patients with other diseases. Moreover, the bacterium type was a positive predictor of survival time compared to other variables. Our data confirm E. coli as a pathogen in patients with gallbladder and pancreatic cancer. Although the influence of bactibilia in developing surgical complications is limited, we consider that its composition is crucial to properly address the antibiotic treatment in biliary tract infections, especially in the elderly.